CVE-2022-50659

In the Linux kernel, the following vulnerability has been resolved:

hwrng: geode - Fix PCI device refcount leak

foreachpcidev() is implemented by pcigetdevice(). The comment of pcigetdevice() says that it will increase the reference count for the returned pcidev and also decrease the reference count for the input pci_dev @from if it is not NULL.

If we break foreachpcidev() loop with pdev not NULL, we need to call pcidevput() to decrease the reference count. We add a new struct 'amdgeodepriv' to record pointer of the pcidev and membase, and then add missing pcidevput() for the normal and error path.